Enable Parallel Sending of Delayed Messages (#1753)

* enable parallel sending of the delayed messages

* added test cases for enqueueToScheduler method with enabled parallel sending

* code style improvement and removed redundant test case

* added retries check

* use concurrentQueue instead of the list for testing purposes

* tests improvements

* fixed concurrency issues

Author: KrawMire

src/DotNetCore.CAP/Processor/IDispatcher.Default.cs

@@ -102,17 +102,28 @@ await Task.WhenAll(Enumerable.Range(0, _options.SubscriberParallelExecuteThreadC
                     await foreach (var nextMessage in _schedulerQueue.GetConsumingEnumerable(_tasksCts.Token))
                     {
                         _tasksCts.Token.ThrowIfCancellationRequested();
-                        try
+
+                        if (_enableParallelSend && nextMessage.Retries == 0)
                         {
-                            var result = await _sender.SendAsync(nextMessage).ConfigureAwait(false);
-                            if (!result.Succeeded)
-                            {
-                                _logger.LogError("Delay message sending failed. MessageId: {MessageId} ", nextMessage.DbId);
-                            }
+                            if (!_publishedChannel.Writer.TryWrite(nextMessage))
+                                while (await _publishedChannel.Writer.WaitToWriteAsync(_tasksCts!.Token).ConfigureAwait(false))
+                                    if (_publishedChannel.Writer.TryWrite(nextMessage))
+                                        break;
                         }
-                        catch (Exception ex)
+                        else
                         {
-                            _logger.LogError(ex, "Error sending scheduled message. MessageId: {MessageId}", nextMessage.DbId);
+                            try
+                            {
+                                var result = await _sender.SendAsync(nextMessage).ConfigureAwait(false);
+                                if (!result.Succeeded)
+                                {
+                                    _logger.LogError("Delay message sending failed. MessageId: {MessageId} ", nextMessage.DbId);
+                                }
+                            }
+                            catch (Exception ex)
+                            {
+                                _logger.LogError(ex, "Error sending scheduled message. MessageId: {MessageId}", nextMessage.DbId);
+                            }
                         }
                     }
 

test/DotNetCore.CAP.Test/DispatcherTests.cs

@@ -16,7 +16,7 @@
 
 namespace DotNetCore.CAP.Test;
 
-public class DispatcherTests 
+public class DispatcherTests
 {
     private readonly ILogger<Dispatcher> _logger;
     private readonly ISubscribeExecutor _executor;
@@ -41,22 +41,22 @@ public async Task EnqueueToPublish_ShouldInvokeSend_WhenParallelSendDisabled()
             SubscriberParallelExecuteThreadCount = 2,
             SubscriberParallelExecuteBufferFactor = 2
         });
-        
+
         var dispatcher = new Dispatcher(_logger, sender, options, _executor, _storage);
 
         using var cts = new CancellationTokenSource();
         var messageId = "testId";
-        
+
         // Act
         await dispatcher.Start(cts.Token);
         await dispatcher.EnqueueToPublish(CreateTestMessage(messageId));
         await cts.CancelAsync();
-        
+
         // Assert
         sender.Count.Should().Be(1);
         sender.ReceivedMessages.First().DbId.Should().Be(messageId);
     }
-    
+
     [Fact]
     public async Task EnqueueToPublish_ShouldBeThreadSafe_WhenParallelSendDisabled()
     {
@@ -150,18 +150,88 @@ public async Task EnqueueToScheduler_ShouldSendMessagesInCorrectOrder_WhenEarlie
         // Act
         await dispatcher.Start(cts.Token);
         var dateTime = DateTime.Now;
-        
+
         await dispatcher.EnqueueToScheduler(messages[0], dateTime.AddSeconds(1));
         await dispatcher.EnqueueToScheduler(messages[1], dateTime.AddMilliseconds(200));
         await dispatcher.EnqueueToScheduler(messages[2], dateTime.AddMilliseconds(100));
 
         await Task.Delay(1200, CancellationToken.None);
         await cts.CancelAsync();
-        
+
+        // Assert
+        sender.ReceivedMessages.Select(m => m.DbId).Should().Equal(["3", "2", "1"]);
+    }
+
+    [Fact]
+    public async Task EnqueueToScheduler_ShouldBeThreadSafe_WhenDelayLessThenMinuteAndParallelSendEnabled()
+    {
+        // Arrange
+        var sender = new TestThreadSafeMessageSender();
+        var options = Options.Create(new CapOptions
+        {
+            EnableSubscriberParallelExecute = false,
+            EnablePublishParallelSend = true,
+            SubscriberParallelExecuteThreadCount = 2,
+            SubscriberParallelExecuteBufferFactor = 2
+        });
+        var dispatcher = new Dispatcher(_logger, sender, options, _executor, _storage);
+
+        using var cts = new CancellationTokenSource();
+        var messages = Enumerable.Range(1, 10000)
+            .Select(i => CreateTestMessage(i.ToString()))
+            .ToArray();
+
+        // Act
+        await dispatcher.Start(cts.Token);
+        var dateTime = DateTime.Now.AddMilliseconds(50);
+        await Parallel.ForEachAsync(messages, CancellationToken.None,
+            async (m, ct) => { await dispatcher.EnqueueToScheduler(m, dateTime); });
+
+        await Task.Delay(3000, CancellationToken.None);
+
+        await cts.CancelAsync();
+
+        // Assert
+        sender.Count.Should().Be(10000);
+
+        var receivedMessages = sender.ReceivedMessages.Select(m => m.DbId).Order().ToList();
+        var expected = messages.Select(m => m.DbId).Order().ToList();
+        expected.Should().Equal(receivedMessages);
+    }
+
+    [Fact]
+    public async Task EnqueueToScheduler_ShouldSendMessagesInCorrectOrder_WhenParallelSendEnabled()
+    {
+        // Arrange
+        var sender = new TestThreadSafeMessageSender();
+        var options = Options.Create(new CapOptions
+        {
+            EnableSubscriberParallelExecute = true,
+            EnablePublishParallelSend = true,
+            SubscriberParallelExecuteThreadCount = 2,
+            SubscriberParallelExecuteBufferFactor = 2,
+        });
+        var dispatcher = new Dispatcher(_logger, sender, options, _executor, _storage);
+
+        using var cts = new CancellationTokenSource();
+        var messages = Enumerable.Range(1, 3)
+            .Select(i => CreateTestMessage(i.ToString()))
+            .ToArray();
+
+        // Act
+        await dispatcher.Start(cts.Token);
+        var dateTime = DateTime.Now;
+
+        await dispatcher.EnqueueToScheduler(messages[0], dateTime.AddSeconds(1));
+        await dispatcher.EnqueueToScheduler(messages[1], dateTime.AddMilliseconds(200));
+        await dispatcher.EnqueueToScheduler(messages[2], dateTime.AddMilliseconds(100));
+
+        await Task.Delay(1200, CancellationToken.None);
+        await cts.CancelAsync();
+
         // Assert
         sender.ReceivedMessages.Select(m => m.DbId).Should().Equal(["3", "2", "1"]);
     }
-    
 
     private MediumMessage CreateTestMessage(string id = "1")
     {

test/DotNetCore.CAP.Test/Helpers/TestThreadSafeMessageSender.cs

@@ -1,4 +1,5 @@
-using System.Collections.Generic;
+using System.Collections.Concurrent;
+using System.Collections.Generic;
 using System.Linq;
 using System.Threading.Tasks;
 using DotNetCore.CAP.Internal;
@@ -8,17 +9,17 @@ namespace DotNetCore.CAP.Test.Helpers;
 
 public class TestThreadSafeMessageSender : IMessageSender
 {
-    private readonly List<MediumMessage> _messagesInOrder = new();
+    private readonly ConcurrentQueue<MediumMessage> _messagesInOrder = [];
 
     public Task<OperateResult> SendAsync(MediumMessage message)
-    { 
+    {
         lock (_messagesInOrder)
         {
-            _messagesInOrder.Add(message);
+            _messagesInOrder.Enqueue(message);
         }
         return Task.FromResult(OperateResult.Success);
     }
-    
+
     public int Count => _messagesInOrder.Count;
     public List<MediumMessage> ReceivedMessages => _messagesInOrder.ToList();
 }